How do fish breathe?: Quick Facts

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Last updated

Oct. 26, 2026

Photos

Respiratory system of a fish

Diagram showing a teleost fish, specifically a perch, with a side view and a labeled cross section. The cross section identifies internal structures including muscle, vertebra, neural spine, nerve cord, dorsal aorta, dorsal and ventral ribs, swim bladder, coelom, and stomach. The side view shows the location of the swim bladder and stomach inside the fish.

South American lungfish

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